Surgical intervention may require the manipulation of one or more medical devices in close proximity to a nerve or nerves, which may risk damage to the nerve tissue. For example, medical devices may be used to cut, extract, suture, coagulate, or otherwise manipulate tissue including tissue near or adjacent to neural tissue. Spinal decompressions, are one type of procedure that may be preformed to remove tissue that is impinging on a spinal nerve. It would be beneficial to be able to cut or manipulate tissue (and especially bone) in a way that avoids or protects nearby structures such as nerves, while allowing precise removal of bone or portions of bones.
For example, a Transforaminal Lumbar Interbody Fusion (“TLIF”) procedure is a surgical technique to stabilize the spinal vertebra and the disc or shock absorber between the vertebras. In this procedure, lumbar fusion surgery creates a solid structure (bone and/or interbody device) between adjoining vertebras, eliminating any movement between the bones. The goal of the surgery is to reduce pain and nerve irritation. The procedure typically involves removal of a great deal of spinal bone, e.g., by cutting through the patients back and removing the facet joints to create an opening into which a spacer or interbody cage can be inserted and filled with bone graft material. Interbody devices such as cages or spacers are typically 8 mm wide to 15 mm wide. Pedicle screws and rods or plates may then be used to fuse the vertebra.
It is common to do a laminectomy as part of the TLIF procedure, in order to provide space for the insertion of the spacer or cage. Other, similar procedures such as Posterior Lumbar Interbody Fusion (PLIF) procedures also involve cutting and removing a region of bone from the spine, such as the removal of a portion of the inferior articulating process (IAP). Removal of these relatively large portions of bone may be difficult, and may require cutting through a substantial amount of otherwise healthy tissue. In addition, the effort of cutting through the bone may damage nearby tissue, including nerve tissue such as nerve roots which are intimately associated with the spine in the dorsal column region being modified. The risks and difficulties of the procedures described above and other such surgical procedure may be exacerbated by the need to make multiple cuts in bone and other tissues, which are typically performed sequentially.
In addition, procedures such as these that involve cutting of spinal bone must be performed in difficult to reach regions, and the surgical procedures performed may necessarily need to navigate narrow and tortuous pathways. Thus, it would be of particular interest to provide devices that are extremely low profile, or are adapted for use with existing low-profile surgical devices and systems. It would also be beneficial to provide devices capable of making multiple, simultaneous cuts at different positions in the tissue (e.g., bone).
Described herein are devices, systems and methods that may address many of the problems and identified needs described above.